Rash and fever illness caused by herpes simplex virus type 1 needs to be distinguished from hand, foot and mouth disease / 病毒学报

An epidemic of rash and fever illnesses suspected of hand, foot and mouth disease (HFMD) occurred in Gansu Province of China in 2008, laboratory tests were performed in order to identify the pathogen that caused this epidemic. Eight clinical specimens collected from the 4 patients (each patient has throat swab and herpes fluid specimens) with rash and febrile illness, were inoculated onto RD and HEp-2 cells for virus isolation, and the viral nucleic acid was then extracted with the positive virus isolates, the dual-channel real-time reverse transcript-polymerase chain reaction (RT-PCR) was performed to detect the nucleic acid of human enterovirus (HEV) in the viral isolates at the same time. For the viral isolates with the negative results of HEV, a sequence independent single primer amplification technique (SISPA) was used for "unknown pathogen" identification. Totally, 6 viral isolates were identified as herpes simplex virus type 1 (HSV-1). Comprehensive analyses results of the clinical manifestations of the patients, epidemiological findings and laboratory test indicated that this epidemic of rash and febrile illness was caused by HSV-1. The differences among the gG region of 6 HSV-1 isolates at nucleotide level and amino acid level were all small, and the identities were up to 98. 8% and 97.9%, respectively, showing that this outbreak was caused by only one viral transmission chain of HSV-1. HSV-1 and other viruses that cause rash and febrile illnesses need differential diagnosis with HFMD. The etiology of rash and febrile illness is sometimes difficult to distinguish from the clinical symptoms and epidemiological data, the laboratory diagnosis is therefore critical.

1,3,4-tri-O-galloyl-6-O-caffeoyl-β-D-glucopyranose, a new anti-proliferative ellagitannin, regulates the expression of microRNAs in HepG(2) cancer cells / 南方医科大学学报

<p><b>OBJECTIVE</b>MicroRNAs (miRNAs) play important roles in cell proliferation, differentiation and apoptosis. 1, 3, 4-tri-O-galloyl-6-O-caffeoyl-β-D-glucopyranose (BJA32515) is a new natural ellagitannin compound extracted from Balanophora Japonica MAKINO. The effect of BJA32515 on the expression of miRNAs in cancer cells has not yet been explored. Objective The present study was carried out to examine the changes in miRNA expression profiles in human HepG(2) hepatocarcinoma cells following BJA32515 exposure.</p><p><b>METHODS</b>The proliferation of BJA32515-exposed HepG(2) cells was assessed using a colorimetric assay (cell counting kit-8). The miRNA expression profile of the cancer cells was analyzed using a miRNA array and quantitative real-time PCR. Apoptosis was assessed by annexin V and propidium iodide staining.</p><p><b>RESULTS</b>BJA32515 inhibited the cell proliferation and increased apoptosis in HepG(2) cancer cells. The exposure to BJA32515 also caused alterations in the miRNA expression profile in the cells, with 33 miRNAs upregulated and 59 down-regulated. The up-regulation of let-7a and miR-29a and the down-regulation of miR-373 and miR-197 were verified by quantitative real-time PCR. CONCLSION: BJA32515-modifed miRNA expression may mediate the antiproliferative effect of this compound in HepG(2) cancer cells.</p>

Trichostatin A inhibits the activation of CD(4)(+) T cells by suppressing CD(28) expression in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the mechanism of trichostatin A(TSA), a histone deacetylase (HDAC) inhibitor, in inhibiting the activation of CD(4)(+) T cells in mice.</p><p><b>METHODS</b>The CD(4)(+) T cells isolated from the spleen of C57BL mice were treated with different concentrations of TSA (2, 20, and 200 nmol/L) for 24 h, and CD(3), CD(28) and interleukin-2 (IL-2) mRNA levels were measured with reverse transcription-polymerase chain reaction. The protein expressions of CD(3), CD(28) and IL-2 were measured by fluorescence-activated cell sorting and ELISA analysis. ZAP70 and PI3K protein expression in CD(4)(+) T cells activated by CD(3) and CD(28) monoclonal antibody were analyzed by Western blotting.</p><p><b>RESULTS</b>TSA dose-dependently inhibited the transcription and protein expression of CD28 in CD(4)(+) T cells and reduced the expression of PI3K protein in activated CD(4)(+) T cells, without showing significant effect on the expression of ZAP70. TSA treatment of the cells also resulted in significantly decreased mRNA and protein expressions of IL-2 (P<0.01).</p><p><b>CONCLUSION</b>TSA can regulate the immunological activity of CD(4)(+) T cells by inducing mRNA and protein expressions of CD(28), which inhibits the activation of the co-stimulatory signal transduction in CD(4)(+) T cells and decreases the secretion of IL-2.</p>

Immunological activity of Streptomyces polysaccharide in normal and immunosuppressed mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the immunological activity of Streptomyces polysaccharide (SMP) on normal and immunosuppressed mice.</p><p><b>METHODS</b>The effect of SMP on the proliferating activity of normal mouse splenocytes was tested in the mixed lymphocyte culture, and the changes of peripheral blood T lymphocytes were evaluated with acid a-naphthyl acetate esterase (ANAE) method. The ratio of Lyt2+ and L3T4+ T cell subsets was measured by flow cytometry.</p><p><b>RESULTS</b>SMP stimulated obvious proliferation of mixed lymphocytes, showed protective effects on T lymphocyte and increased the ratio of Lyt2+ and L3T4+ cell subsets to nearly normal level in immunosuppressed mice.</p><p><b>CONCLUSIONS</b>SMP can regulate the immune function in mice.</p>

Inhibitory effect of polysaccharides on the six-alpha-helix bundle formation of HIV gp41 protein / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the in vitro inhibitory effect of expolysaccharides from Streptomyces, polysaccharides of Ganoderma lucidum and rice bran on six-alpha-helix bundle formation of HIV gp41 protein.</p><p><b>METHODS</b>The amount of six-alpha-helix bundle formed in the presence of N36 and C34 was tested by ELISA in response to treatments with different doses of polysaccharides.</p><p><b>RESULTS</b>Expolysaccharides from Streptomyces potentially inhibited six-alpha-helix bundle formation with the effective concentration (IC(50)) of 145.48-/+7.25 mg /L. Polysaccharides of Ganoderma lucidum and rice bran showed no effect on the six-alpha-helix bundle formation.</p><p><b>CONCLUSION</b>Expolysaccharides from Streptomyces can inhibit the six-alpha-helix bundle formation of HIV gp41, whereas polysaccharides of Ganoderma lucidum and rice bran do not exhibit such activity.</p>

Purification of a new phospholipase A2 homologue from Agkistrodon blomhoffii siniticus and its effects on gene expression profile of Hep3B cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To isolate and purify a new phospholipase A2 (PLA2) homologue from Agkistrodon blomhoffii siniticus and investigate its effects on the gene expression profile of Hep3B cells.</p><p><b>METHODS</b>The PLA2 homologue was isolated and purified by reverse-phase high-performance liquid chromatography (HPLC) and its purity was determined also by HPLC. The relative molecular mass of the homologue was measured by electrospray ionization mass spectrum. The gene expression profile of Hep3B cells was detected with gene chip after exposure of the cells to 139 microg/ml PLA2 homologue for 12 h.</p><p><b>RESULTS</b>The purity of the PLA2 homologue was 97.2%, whose relative molecular mass was 13,900. After exposure of Hep3B cells to 139 microg/ml PLA2 homologue for 12 h, 19 genes were down-regulated and 20 up-regulated in the cells. The genes showing altered expressions in response to the exposure were mainly involved in cell cycle control and DNA damage repair, cell apoptosis and senescence, production of signal transduction molecules and transcription factors, cell adhesion, angiogenesis, and tumor invasion and metastasis.</p><p><b>CONCLUSIONS</b>The PLA2 homologue induces alterations in the expression of a wide variety of genes involved in the growth and metastasis of tumor cells. The results of this study provide clues for further study of the possible mechanism for the action of PLA2 homologue on Hep3B cells.</p>